JP2011225051A - Radio communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio communication system capable of securing high communication establishment property even when the space for arranging a communication master is limited.SOLUTION: A secondary antenna 28 with an antenna of an out-vehicle reader/writer 10 as a primary antenna is provided on a door glass 27 of a vehicle 1. A cellular phone 2 is used as a vehicle key, and is operated by holding it over the secondary antenna 28 of the door glass 27 when a door lock is locked/unlocked. At this time, the communication between the primary antenna 12 of the out-vehicle reader/writer 10 and the secondary antenna 28 of the door glass 27 is established by electromagnetic induction, and also the communication between the secondary antenna 28 and a tag 21 of the cellular phone 2 is established by electromagnetic induction. Therefore, the tag 21 is activated by a drive radio wave Sv from the out-vehicle reader/writer 10, and then the cellular phone 2 is certified by an ID code replied from the tag 21.

Description

  The present invention relates to a wireless communication system that performs authentication of a communication terminal wirelessly.

  In recent years, a mobile phone key system has been devised in which a vehicle ID code is registered in a mobile phone and the mobile phone is used as a vehicle key (see Patent Document 1, etc.). For example, a communication technology such as Felica (registered trademark) is applied to this system. When the cellular phone key system is applied to a door entry system, for example, a reader / writer is disposed on the upper surface of the door trim. Then, if ID collation (holding collation) is established by holding the mobile phone from the outside of the vehicle through the door glass to the outside reader / writer, door locking / unlocking is permitted or executed.

JP 2007-137135 A

  By the way, the radio waves that can be transmitted by the reader / writer have a relatively small area such as about several tens of centimeters. Therefore, even if you intend to hold the mobile phone, it is fully assumed that communication is not actually established. In this case, the user will be required to repeat the holding operation. There was a request to secure the feasibility. However, since the area of the upper surface of the door trim is limited, there is a current situation that there is a limit to this even if the antenna area of the reader / writer is increased in order to ensure the communication feasibility of the reader / writer.

  An object of the present invention is to provide a wireless communication system capable of ensuring high communication establishment even if there is a space limitation at the location where the communication master is arranged.

  In order to solve the above problems, in the present invention, a communication master provided in a vehicle and its communication terminal can communicate with each other by short-range wireless communication, and the communication terminal is triggered by an inquiry from the communication master. In a wireless communication system in which a signal is sent back to the communication master for communication, a movable antenna provided in the vehicle is provided with a secondary antenna that uses the antenna of the communication master as a primary antenna, and transmission and reception of the primary antenna The gist is to execute the short-range wireless communication by relaying a radio wave by the secondary antenna.

  According to this configuration, the movable glass is provided with the secondary antenna, and short-range wireless communication between the communication master and the communication terminal is performed via the secondary antenna. Therefore, the communication area of the primary antenna of the communication master can be pulled out to the communication terminal side by the secondary antenna. Moreover, since the secondary antenna is provided on the movable glass originally having a large area, it is possible to increase the antenna area of the secondary antenna without worrying about the arrangement space.

  Therefore, even when the arrangement space of the communication master is limited and the area of the primary antenna of the communication master cannot be increased, the communication area of the communication master can be widened by the secondary antenna. . Therefore, even if there is a space limitation at the location where the communication master is disposed, it is possible to ensure communication between the communication master and the communication terminal, that is, communication feasibility of short-range wireless communication.

  In the present invention, the movable glass is a door glass of the vehicle, and the secondary antenna is disposed at a position that enters a communication area of the primary antenna when the door glass is fully closed. It is a summary.

  According to this configuration, when the door glass is in a fully closed state, the secondary antenna is used and authentication of the communication terminal via the secondary antenna can be performed. Therefore, if the establishment of authentication is the start condition for unlocking and unlocking the vehicle door lock, the communication itself is not executed if the door glass is in the open state, so that the door lock is locked with the door glass open. It can be made difficult to occur.

The gist of the present invention is that the secondary antenna is composed of one sheet-like component in which an antenna line and a resonant capacitor are mounted on a flexible substrate.
According to this configuration, since the secondary antenna can be a single sheet-like retrofit component, for example, even if the vehicle does not have a secondary antenna, the retrofit component is used as the movable glass of the vehicle. The secondary antenna can be retrofitted to the vehicle by a simple operation of attaching to the vehicle.

In the present invention, in response to the inquiry from the communication master, the communication terminal returns unique identification information to the communication master, authenticates the communication terminal with the identification information, and based on a result of establishment of the authentication. The gist is to perform door lock control of the vehicle.
According to this configuration, the vehicle door lock can be controlled based on the authentication result of the communication terminal.

  The gist of the present invention is that at least the primary antenna of the communication master is embedded in a door trim of the vehicle.

  According to this configuration, since at least the primary antenna of the communication master is hidden inside the door trim, the appearance near the door trim is improved. Further, even if at least the primary antenna of the communication master is hidden in the door trim in this way, the communication area of the primary antenna is pulled out by the secondary antenna, so that the communication establishment of authentication is ensured.

  According to the present invention, high communication establishment can be ensured even if there is a space limitation at the location where the communication master is arranged.

The block diagram which shows schematic structure of the mobile telephone key system in one Embodiment. The perspective view which shows the external appearance of a secondary antenna. The side view of the vehicle which shows the arrangement position of a secondary antenna. Sectional drawing which shows the outline of a front seat secondary antenna. Sectional drawing which shows the outline of a rear seat secondary antenna. The circuit diagram which shows the equivalent circuit of a reader / writer and a secondary antenna. The operation | movement figure which shows the state which held the mobile phone over the front seat secondary antenna. The circuit diagram which shows the equivalent circuit of a reader / writer, a secondary antenna, and a tag.

An embodiment of a radio communication system embodying the present invention will be described below with reference to FIGS.
As shown in FIG. 1, the vehicle 1 is provided with a mobile phone key system 3 that uses the mobile phone 2 as an electronic key by registering the ID code of the vehicle 1 in the mobile phone 2. For the communication of the cellular phone key system 3, for example, RFID (Radio Frequency IDentification) is used as near field communication (NFC). For example, FeliCa (registered trademark) or the like is used for the RFID. For example, HF (High Frequency) is used as the frequency of the RFID. The mobile phone 2 corresponds to a communication terminal.

  The cellular phone key system 3 performs ID (Identification) verification of the cellular phone 2 by “holding” the cellular phone 2 close to the vicinity of the vehicle 1. That is, when the mobile phone 2 receives the drive radio wave Sv from the vehicle 1 while holding the mobile phone 2 close to the vehicle 1, the mobile phone 2 returns the ID signal Sid to the vehicle 1 with the drive radio wave Sv as a power source, and the ID signal The ID verification of the mobile phone 2 is performed by the ID code included in Sid, that is, so-called holding verification. The driving radio wave Sv constitutes inquiry and transmission / reception radio waves, and the ID signal Sid constitutes identification information and transmission / reception radio waves.

  The mobile phone key system 3 includes a door entry function that performs locking and unlocking of the door lock if the verification is established outside the vehicle, and a push-operated engine installed in the vehicle if the verification is established in the vehicle. There is a one-push engine start function in which the engine is started simply by pressing the switch 4. The engine switch 4 can perform not only engine start operation but also power supply transition operation of the vehicle 1.

  The vehicle 1 is provided with an ID verification device 5 that performs ID verification with the mobile phone 2, a door lock device 6 that manages the locking and unlocking of the door lock, and an engine starter 7 that manages the operation of the engine. These are connected via the in-vehicle bus 8. The ID verification device 5 is provided with a verification ECU (Electronic Control Unit) 9 as a control unit of the ID verification device 5. When the verification ECU 9 obtains an ID code from the mobile phone 2 by short-range wireless communication, the verification ECU 9 performs ID verification by comparing the ID code with its own.

  A vehicle outside reader / writer 10 capable of short-range wireless communication with the mobile phone 2 located outside the vehicle is provided near the door of the vehicle 1. The outside reader / writer 10 is a kind of communication device capable of transmitting and receiving radio waves by electromagnetic induction with a terminal such as a non-contact IC card. The main body 35 of the outside reader / writer 10 is provided with a communication circuit 11 that performs modulation of transmission radio waves, demodulation / amplification of reception radio waves, and the like. The outside reader / writer 10 constitutes a communication master.

  An antenna 12 of the outside reader / writer 10 is connected to the communication circuit 11. As the antenna 12, a kind of loop antenna of a magnetic field antenna in which a plurality of antenna wires (antenna elements) are wound in an annular shape is used. The antenna 12 includes a series resonance circuit including a coil 13 and a resonance capacitor 14. The antenna 12 is a transmission / reception antenna that can both transmit and receive radio waves.

  In the vehicle, for example, the center console is provided with an in-car reader / writer 15 capable of short-range wireless communication with the mobile phone 2 brought into the car. The in-car reader / writer 15 includes a communication circuit 16 and an antenna 17 like the in-car reader / writer 10, and the antenna 17 also includes a series resonance circuit of a coil 18 and a capacitor 19. These reader / writers 10 and 15 are capable of both transmission of the drive radio wave Sv and reception of various radio waves transmitted from the mobile phone 2, that is, mutual communication. The in-car reader / writer 15 constitutes a communication master.

  On the other hand, the mobile phone 2 is provided with a terminal control unit 20 that controls various operations of the mobile phone 2. The mobile phone 2 is provided with a tag 21 that performs near field communication with the reader / writers 10 and 15. The tag 21 is provided with a communication control circuit 22 that manages the operation of the tag 21. In the communication control circuit 22, an ID code is registered so that the mobile phone 2 functions as a vehicle key.

  A transmission / reception antenna 23 is connected to the communication control circuit 22 as an antenna of the tag 21. As the transmission / reception antenna 23, a loop antenna which is a kind of magnetic field antenna is used. The transmission / reception antenna 23 includes a series resonance circuit including a coil 24 in which an antenna wire is wound in an annular shape and a resonance capacitor 25. The tag 21 is activated when the driving radio wave Sv is received from the reader / writer 10 or 15 by the short-range wireless communication, and the ID signal Sid including the ID code registered in the tag 21 is transmitted to the reader / writer 10 or 15 via the short-range wireless communication. Reply to

  The vehicle 1 is provided with a reader / writer control ECU 26 that controls the operations of the reader / writers 10 and 15. The reader / writer control ECU 26 intermittently transmits the drive radio wave Sv from the outside reader / writer 10 when the vehicle 1 is parked or stopped. And reader / writer control ECU26 will transfer this ID code to collation ECU9, if ID signal Sid is received from tag 21 as a response of drive electric wave Sv. When the collation ECU 9 inputs the ID code from the reader / writer control ECU 26, the collation ECU 9 collates the ID code and determines whether or not the mobile phone 2 is a regular communication partner.

  In the cellular phone key system 3, a secondary antenna 28 is attached to the door glass 27 of the vehicle 1, and the radio wave of the outside reader / writer 10 is relayed by the secondary antenna 28 to increase the communication area of the outside reader / writer 10. Secondary antenna relay type. In the case of this example, the effective distance area of the reader / writer 10 outside the vehicle is increased by extending the communication distance of the reader / writer 10 outside the vehicle to the mobile phone 2 side by the secondary antenna 28 and increasing the antenna area of the secondary antenna 28. Thereby, the communication area of the reader / writer 10 outside the vehicle is widened, and the communication feasibility of the collation is ensured. The door glass 27 corresponds to a movable glass.

  As shown in FIG. 2, the secondary antenna 28 is provided with a sheet-like flexible substrate 29. The flexible substrate 29 is a substrate that can be freely bent and deformed. On the mounting surface of the flexible substrate 29, an antenna pattern 30 in which a plurality of antenna wires (antenna elements) are wound in an annular shape and a resonance capacitor 31 that connects a pair of terminal ends of the antenna pattern 30 are mounted. Therefore, the secondary antenna 28 is a loop antenna which is a kind of magnetic field antenna. The antenna area of the secondary antenna 28 is formed to be larger than the antenna 12 of the outside reader / writer 10, that is, the primary antenna 12.

  As shown in FIGS. 3 and 4, a front seat secondary antenna 28a is attached to the back surface of the door glass 27a of the front seat door 32 as a secondary antenna 28 for the front seat door glass 27a. The front seat means a driver seat and a passenger seat. The front seat door glass 27a can be opened and closed by sliding in the vertical direction by operating a door opening / closing switch (not shown) in the vehicle. The front seat secondary antenna 28a is disposed at a position below the vehicle body and closer to the rear side on the back surface of the front seat door glass 27a.

  As shown in FIG. 4, a front seat outside-vehicle reader / writer 10 a is embedded in a door trim 33 of the front seat door 32. The front seat secondary antenna 28a is disposed at a position where the front seat door glass 27a enters the communication area of the primary antenna 12 of the outside reader / writer 10a when the front seat door glass 27a is in a fully closed state or a substantially fully closed state. For this reason, although the communication area of the primary antenna 12 itself of the outside reader / writer 10a is formed only in a small area, the communication area of the outside reader / writer 10a becomes the front seat door by relaying radio waves by the front seat secondary antenna 28a. It is amplified to a wide area that fills one area of the glass 27a.

  As shown in FIGS. 3 and 5, a rear seat secondary antenna 28b is attached to the rear surface of the door glass 27b of the rear seat door 34 as a secondary antenna 28 for the rear seat door glass 27b. The rear seat means the rear right seat and the rear left seat. The rear seat door glass 27b can also be opened and closed by sliding in the vertical direction by operating a vehicle door opening / closing switch (not shown). The rear seat secondary antenna 28b is disposed at a position above the vehicle body and closer to the front side on the back surface of the rear seat door glass 27b.

  As shown in FIG. 5, an outside reader / writer 10 b for the rear seat is attached to the door edge of the vehicle body ceiling 1 a. The rear seat secondary antenna 28b is disposed at a position that enters the communication area of the primary antenna 12 of the outside reader / writer 10b when the rear seat door glass 27b is in a fully closed state or a substantially fully closed state. For this reason, although the communication area of the primary antenna 12 itself of the outside reader / writer 10b is formed only in a small area, the communication area of the outside reader / writer 10b becomes a rear seat door by relaying radio waves by the rear seat secondary antenna 28b. It is amplified to a wide area that fills one area of the glass 27b.

  The secondary antenna 28 is a retrofitted sheet-like component in which a series resonance circuit (an antenna pattern 30 and a capacitor 31) is mounted on a single flexible substrate 29. Therefore, when the secondary antenna 28 is not attached to the door glass 27 of the vehicle 1, the sheet-like secondary antenna 28 is aligned with the outside reader / writer 10 and attached to the back surface of the door glass 27. wear.

  Now, when the vehicle 1 is parked (engine stopped, door lock locked), the outside reader / writer 10 intermittently transmits the driving radio wave Sv in order to investigate whether the mobile phone 2 exists around the vehicle. Send. Here, as shown in the equivalent circuit of FIG. 6, the primary antenna 12 and the secondary antenna 28 of the outside reader / writer 10 are coupled by electromagnetic induction, and the driving radio wave Sv of the primary antenna 12 is connected to the secondary antenna 28. Thus, it is transmitted over a wide range via the secondary antenna 28.

  In the case of this example, the communication distance of the primary antenna 12 is extended by the secondary antenna 28, so that the driving radio wave Sv of the primary antenna 12 flies farther. In addition, since the antenna area of the secondary antenna 28 is formed larger than the antenna area of the primary antenna 12, the mobile phone 2 has a wider area than when only the primary antenna 12 is used. The effective area is increased.

  Here, for example, when the driver gets on from the front seat door 32, as shown in FIG. 7, the driver performs an operation of holding the mobile phone 2 possessed by the driver over the front seat secondary antenna 28a from the outside of the vehicle. At this time, as shown in the equivalent circuit of FIG. 8, communication is established between the primary antenna 12 and the front seat secondary antenna 28a by electromagnetic induction, and communication between the front seat secondary antenna 28a and the tag 21 is performed by electromagnetic induction. Therefore, short-distance wireless communication between the front seat outside-vehicle reader / writer 10a and the tag 21 is established. Therefore, the tag 21 is activated by the driving radio wave Sv from the front seat outside-vehicle reader / writer 10a, and returns an ID signal Sid to the vehicle 1 as a response.

  When the tag 21 returns the ID signal Sid, the front seat outside-vehicle reader / writer 10a receives the ID signal Sid via the secondary antenna 28a. When the front seat outside-vehicle reader / writer 10 a receives the ID signal Sid by the primary antenna 12, it transfers the ID code included in the ID signal Sid to the verification ECU 9. When the verification ECU 9 verifies the ID code of the tag 21 and confirms that ID verification is established, the verification ECU 9 unlocks the door lock. The operation at the time of locking the door lock is basically the same as the unlocking operation of the door lock, and the details are omitted.

  As described above, in this example, when the secondary antenna 28 is attached to the inner surface of the door glass 27 and the mobile phone 2 is held over the reader / writer 10 outside the vehicle, the reader / writer 10 and the mobile phone 2 are connected between the reader / writer 10 outside the vehicle. The exchanged radio wave is relayed by the secondary antenna 28 and held outside the vehicle, and collation is executed. Therefore, the communication area of the outside reader / writer 10 can be pulled out to the mobile phone 2 side (user side) by the secondary antenna 28. Further, since the secondary antenna 28 is attached to the door glass 27 that originally has a large area, the antenna area of the secondary antenna 28 can be increased without worrying about the arrangement space.

  By the way, when the outside reader / writer 10 is attached to the door trim 33, since the door trim 33 does not have a sufficient area, the size of the outside reader / writer 10, that is, the antenna area of the primary antenna 12 cannot be increased, and communication establishment is possible. Even if you try to improve, you can not satisfy this. However, if radio waves are relayed by the secondary antenna 28 as in this example, there is a case where the arrangement area of the outside reader / writer 10 is limited and the antenna area of the outside reader / writer 10 cannot be increased. However, the communication area of the outside reader / writer 10 can be widened by the secondary antenna 28. Therefore, it is possible to ensure the communication feasibility of the hand-check.

According to the configuration of the present embodiment, the following effects can be obtained.
(1) The secondary antenna 28 of the reader / writer 10 outside the vehicle is attached to the door glass 27, and radio waves are relayed by the secondary antenna 28, so that the mobile phone 2 and the reader / writer 10 outside the vehicle are checked against each other. Therefore, even if the arrangement space of the outside reader / writer 10 is limited and the antenna area of the outside reader / writer 10 cannot be increased, the outside reader The communication area of the writer 10 can be widened. For this reason, since the admissibility of the holding position of the mobile phone 2 appears, it is possible to ensure the communication establishment of the holding check.

  (2) When the secondary antenna 28 is attached to the door glass 27, the height position of the secondary antenna 28 that faces the outside reader / writer 10 when the door glass 27 is in the fully closed state (substantially fully closed state) is set. It was set as the sticking position. Therefore, since it is possible to perform the collation only when the door glass 27 is in the fully closed state, it is possible to make it difficult to cause a situation in which the door lock is locked while the door glass 27 is in the open state.

  (3) Since the secondary antenna 28 is a single sheet-like retrofitting part, for example, even if the vehicle 1 originally does not have the secondary antenna 28, the secondary antenna 28 is used as the door glass 27. The secondary antenna 28 can be attached to the vehicle 1 by a simple operation of sticking to the vehicle 1.

  (4) Since the secondary antenna 28 is a single sheet component, the secondary antenna 28 can be a single unit component. Therefore, even if the secondary antenna 28 is attached to the door glass 27 so that the glass surface is the antenna installation location, the secondary antenna 28 is integrally attached to the door glass 27, so one of the wirings is attached to the movable side, There is no need for a part structure in which the other side of the wiring is attached to the fixed side. Therefore, there is no need for wiring and the like, and there is no need to worry about disconnection or the like.

  (5) Since the outside reader / writer 10 is hidden inside the door trim 33, the appearance of the vicinity of the door trim 33 is improved. Even if the outside reader / writer 10 is hidden in the door trim 33 in this way, the communication area of the outside reader / writer 10 is pulled out by the secondary antenna 28, so that it is possible to ensure the establishment of communication for holding and collating.

(6) Since the secondary antenna 28 is a sheet-like component, the shape can be freely changed such as bending or rounding according to the shape of the sticking destination.
Note that the embodiment is not limited to the configuration described so far, and may be modified as follows.

Only the outside reader / writer 10 is not limited to the secondary antenna relay type, and may be applied to the in-vehicle reader / writer 15.
The attachment position of the secondary antenna 28 to the door glass 27 is not limited to the position illustrated in the embodiment, and may be changed to another position.

The secondary antenna 28 is not limited to a retrofitted part, and may be an antenna integrated into the door glass 27.
-On the glass surface of the door glass 27, a pattern, a character, or the like for notifying the holding position may be drawn at the location where the secondary antenna 28 is disposed.

The tag 21 is not limited to being an IC chip independent from the terminal control unit 20, and the function of the tag 21 may be incorporated in the terminal control unit 20.
The arrangement position of the outside reader / writer 10 is not limited to the inside of the door trim 33 or the vehicle body ceiling 1a, and may be a vehicle body pillar, for example.

  The secondary antenna 28 is not limited to the antenna pattern 30 and the resonance capacitor 31 that are both provided on the door glass 27. For example, only the antenna pattern 30 may be provided on the door glass 27 and the resonance capacitor 31 may be provided on the door trim 33.

The secondary antenna 28 is not limited to a single sheet-like component, and may be an unfoldable antenna using a plate-like substrate, for example.
The communication terminal is not limited to the mobile phone 2 and may be any terminal as long as it can transmit the ID code wirelessly.

-Near field communication is not limited to RFID, and other communication methods can be employed.
The movable glass is not limited to the door glass 27 and may be any glass that moves in at least two modes.

The transmitted / received radio wave is not limited to the driving radio wave Sv and the ID signal Sid, and various radio waves according to the communication format can be adopted.
Each antenna (secondary antenna 28) of the cellular phone key system 3 is not limited to a loop antenna, and other antennas such as a dipole antenna can also be used.

  The frequency of the cellular phone key system 3 is not limited to HF, and for example, LF (Low Frequency), UHF (Ultra High Frequency), or the like may be used. Further, the frequency of the radio wave may be different between the two-way communication going and returning.

-The ID code of the tag 21 may be changeable in registration.
Next, technical ideas that can be grasped from the above-described embodiment and other examples will be described below together with their effects.

  (A) In any one of claims 1 to 5, the secondary antenna has an antenna area larger than that of the primary antenna. According to this configuration, since the communication area of the primary antenna is widened by the secondary antenna, higher communication establishment is complemented.

  (B) In any one of claims 1 to 5 and the technical idea (A), the secondary antenna is adhered to the inner surface of the movable glass. According to this configuration, there is no fear that the secondary antenna is peeled off by a third party or the like.

  DESCRIPTION OF SYMBOLS 1 ... Vehicle, 2 ... Mobile phone as a communication terminal, 10 (10a, 10b) ... Outside reader / writer which comprises communication master, 12 ... Primary antenna, 15 ... In-vehicle reader / writer which comprises communication master, 17 ... Antenna, 27 (27a, 27b) ... door glass as movable glass, 28 (28a, 28b) ... secondary antenna, 29 ... flexible substrate, 30 ... antenna pattern as antenna wire, 31 ... resonance capacitor, 33 ... door trim, Sv ... Inquiry and drive radio wave constituting transmission / reception radio wave, Sid... Identification information and ID signal constituting transmission / reception radio wave.

Claims (5)

A communication master provided in a vehicle and its communication terminal can communicate with each other by short-range wireless communication, and the communication terminal returns a signal to the communication master and communicates in response to an inquiry from the communication master In a communication system,
A short-range wireless communication is provided by providing a movable antenna provided on the vehicle with a secondary antenna having the communication master antenna as a primary antenna, and relaying transmission / reception radio waves of the primary antenna by the secondary antenna. A wireless communication system, characterized in that The movable glass is a door glass of the vehicle, and the secondary antenna is disposed at a position that enters a communication area of the primary antenna when the door glass is fully closed. The wireless communication system according to claim 1. The wireless communication system according to claim 1 or 2, wherein the secondary antenna is composed of one sheet-like component in which an antenna line and a resonant capacitor are mounted on a flexible substrate. In response to the inquiry from the communication master, the communication terminal returns unique identification information to the communication master, authenticates the communication terminal with the identification information, and based on the result of establishment of the authentication, the door of the vehicle The wireless communication system according to any one of claims 1 to 3, wherein lock control is performed. The wireless communication system according to any one of claims 1 to 4, wherein at least the primary antenna of the communication master is embedded in a door trim of the vehicle.

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